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Full text of "The Cambridge Natural History"

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In the Marsupials the pouch shelters the young, which are
born in an exceedingly imperfect state, minute, nude, and blind,
with a " larval" mouth fitted only to grasp in a permanent
fashion the teat, upon which they are carefully fixed by the
parent. But even later the pouch is made use of as a temporary
harbour of refuge : from the pouch of female Kangaroos at the
Zoological Gardens may frequently be observed to protrude the tail

FIG. 3.óRcJudna li-ystritc, A, Lower surface of brooding" female ; Bj dissection showing
a dorsal view of tlie pouch and mammary glands ; "H", the two tufts of hair iu the
lateral folds of the mammary pouch from which the secretion flows. &.m, Pouch ;
cl, cloaca ; g.m, group.1? of mammary glands. (From Wiedersheim's Comparative
Anatomy, after W. Haacke.)
and hind-legs of a young Kangaroo as big as a Cat., and perfectly
well able to take care of itself.
In the Monotremata (in JScJiidna) there is a deep fold of
the skin which lodges the unhatched egg, and into which the
mammary glands open, one on either side. This structure is only
periodically developed, and arises from two rudiments, one corre-
sponding to each mammary area ; but in the female with eggs or
young there is but a single deep depression, which occupies the
same region of the body as the marsupial pouch of the Mar-